To more efficiently transmit digital audio data on low bandwidth data networks, or to store larger amounts of digital audio data in a small data space, various data compression or encoding systems and techniques have been developed. Many such encoded audio systems use as a main element in data reduction the concept of not transmitting, or otherwise not storing portions of the audio that might not be perceived by an end user. As a result, such systems are referred to as perceptually encoded or "lossy" audio systems.
However, as a result of such data elimination, perceptually encoded audio systems are not considered "audiophile" quality, and suffer from processing limitations. To overcome such deficiencies, a method and system have been developed to encode digital audio signals in a loss-less fashion, which is more properly referred to as "component audio" rather than perceptual encoding, since all portions or components of the digital audio signal are retained. Such a method and system are described in detail in U.S. patent application Ser. No. 08/771,790 entitled "Method And System For Lossless Encoding Of Digital Audio Data", which was filed on the same date and assigned to the same assignee as the present application, and is hereby incorporated by reference.
Well known processing techniques for linear encoded digital audio signals permit the mixing of music underneath a voice recording, or the mixing of many different musical instrument sounds in a multi-track recording system. While relatively simple, the computational power required for such processing is large.
However, perceptually encoded audio systems were designed for data packing and transmission purposes rather than for production purposes such as mixing. As a result, no such processing exists in the perceptual or component encoded signal path. Therefore, such audio must first be decoded to linear audio for mixing, and then re-encoded.
Thus, there exists a need for a method, system and product for mixing encoded audio signals directly, particularly perceptually encoded audio signals. The computations associated with such a method, system and product would be much less than mixing linear encoded full-range, full fidelity audio signals.